PRIME Minister Gordon Brown today defended the decision to go ahead with a third runway at Heathrow.
In a late-morning statement to MPs, Transport Secretary Geoff Hoon will announce the Government's backing for the 9 billion expansion – including a sixth terminal – with "sweeteners" attached to try to appease those opposed to airport expansion.
Shortly before the announcement, Mr Brown said the needs of the economy and the environment had to be balanced.
In Berlin, where he is meeting German chancellor Angela Merkel, Mr Brown said: "It is always our desire to make sure that we protect the economic future of the country while at the same time meeting the very tough environmental conditions that we have set ourselves for noise and pollution and for climate change."
In an attempt to mollify the project's opponents, Mr Hoon will also announce plans for a high-speed rail line linking Heathrow with central London.
He will also say that planes using the 7,200ft runway – likely to be completed around 2019/20 – must conform to strict noise and air quality targets.
Airlines, big business and some unions are backing Heathrow expansion, which they say could create 65,000 jobs and is essential for London's and Britain's future economic well-being.
Nearly 50 Labour backbenchers are against the plan, as are the Conservatives and Lib Dems, who prefer improved rail links.
The go-ahead for expansion will also dismay local councils, residents and green groups. The runway will lead to the demolition of around 700 homes and will effectively destroy the village of Sipson.
The anti-expansion lobby disputes the Government contention that expansion will be worth billions of pounds a year to the British economy.
They also believe that expansion will have a detrimental effect on air quality and noise in the Heathrow area.
The expansion will be subject to a planning inquiry and the planning process could be complicated by the fact that Greenpeace has bought a small section of land and is dividing it between hundreds of individuals.
The Conservatives favour a rail link from Heathrow to the north of England, which they say would mean thousands fewer flights a year to and from the west London airport.
Shadow transport secretary Theresa Villiers said a go-ahead for a third runway would "prove that Gordon Brown is deaf to the concerns of his own party and millions of people living under the flight path".
Martin Salter, Labour MP for Reading West and a leading opponent of the expansion, said: "There will be attempts to sweeten the pill, but it is difficult to conceive of measures that can mitigate the environmental effect of increasing flights out of Heathrow, over one of the most densely-populated parts of England, by 50%."
Greenpeace executive director John Sauven said the go-ahead "will shred the last vestiges of Brown's environmental credibility".
Friends of the Earth said expanding Heathrow would "shatter the Government's international reputation on climate change and seriously threaten the UK's ability to meet its targets for cutting emissions".
Labour MP John McDonnell, whose constituency includes the airport, said: "The Government's announcement is not the end of the battle against the third runway, it is just the beginning.
"Opponents will use every mechanism possible to prevent the runway going ahead, including campaigns in Parliament, in the courts, in the planning process, in the media and if necessary in direct action.
"If the Government is not willing to listen to Parliament or the people, then there is no other option but to mobilise the largest coalition of public opposition and protest to halt this disastrous proposal in its tracks."
Green Party leader Caroline Lucas said: "This decision demonstrates a complete contempt for the environment, for the health of UK citizens and for our democratic processes.
"A third runway will have disastrous consequences for residents in my South East constituency – leading to serious environmental damage and social upheaval through increased pollution, and the destruction of local communities."
Heathrow-based anti-expansion group Hacan said a decision to give the green light was "the last gasp of the dinosaurs" and would be fought all the way.
Hacan added that on Saturday hundreds of people are expected to converge on the departures concourse at Heathrow Terminal 5 for a "flash mob" protest in which campaigners will all reveal red T-shirts emblazoned with the words Stop Airport Expansion.
Geraldine Nicholson, chairman of NoTRAG (No Third Runway Action Group), said: "The Government has not listened to the views of the people.
"Once again it is siding with big business. Our support has come from all quarters and continues to grow every day. This decision will only intensify the determination of the opposition to expansion at Heathrow."
Sipson resident Linda McCutcheon said she had spent years fighting the expansion plans.
She told Sky News: "We are going to win. Hopefully, there will be a general election soon and this uncaring and unlistening Government will be voted out and the expansion will not go ahead. We are looking forward to that."
Paul Charles, communications director of Sir Richard Branson's airline Virgin Atlantic, said: "We welcome the decision for a third runway, subject to the right noise and air quality standards being met.
"The runway will help Britain to create jobs and remain central to the global economy."